Yamaha YP-D4 DD Turntable speed issues

Hi, recently I restored a Yamaha YP-D4 direct drive turntable. From that grey plastic "veneer" I made it to a piano black. All great, the turntable is all set up.
The problem is that the strobe is not spot on but it wobbles a little left and right.
I set the motor control as in the manual but I cannot make it to be spot on.
Anyone, any ideas ?

I'm attaching the service manual and a speed test done with a phone app.


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I'm late to answer, but I have an Onkyo DD which had unstable speed, with three things fixing it. First was the common and obvious one of cleaning the speed control potentiometers. This had a small effect. Second, clean the speed control switches (33/45) which on this table, are the kind that cancel each other. This made a bigger difference. But finally, remove the motor rotor and lubricate the bearing - now perfect.
Hi, never too late they say :).
The cleaning of switches pots and other parts didn't do much for my problem.
I tries replacing caps and that would not solve it as well.
The only thing that solved the problem was replacing the small signal Toshiba transistors with new ones.
I was convinced that I must have the original transistors in there because they where "ok" by only measuring them with a multimeter but it seems that they where leaky or at least one or two of them. Keeping in mind that this turntable was made in 1979...well.

So maybe this will help some of you who do such projects or other Yamaha turntables.